Cracked glass

[lost.and.lonely.physicist@gmail.com]

Hello everyone

A cafe I visit often has large glass windows. Recently, one of them
cracked - it appears that something went thru it, puncturing a small
hole, causing the entire rectangular piece of glass to crack (but not
shatter) into a cobweb-like pattern, centered around the hole.

I'm curious how one might describe such a phenomenon -- both the
cobweb-like pattern of cracked glass, how it formed in the first place,
in what way the formation of the pattern is dependent on boundary
conditions (the glass window is held in a rectangular wooden frame) and
what sort of aggregate properties one might be able to derive out of
such a seemingly complicated system.

Thanks for any insight.